Clinical outcomes of the PAUL® glaucoma implant for secondary glaucoma

Secondary glaucoma encompasses a broad spectrum of disease entities arising from diverse ocular pathologies and is often refractory to conventional treatment. Glaucoma drainage devices (GDDs) have therefore become an important surgical option. This study evaluates the efficacy and safety of the PAUL® Glaucoma Implant (PGI) across a broad spectrum of secondary glaucoma types.

This retrospective observational cohort study included 96 eyes from 92 patients who underwent PGI implantation for secondary glaucoma between April 2021 and September 2024, with a minimum follow-up of 12 months. Secondary glaucomas were categorized into neovascular, uveitic, post-vitrectomy, traumatic and other types. Surgical success was defined according to World Glaucoma Association intraocular pressure (IOP) thresholds (≤21, ≤18, ≤15, and ≤12 mmHg), with failure defined by IOP above threshold, hypotony-related complications, need for further glaucoma surgery, or device explantation.

At one year, 83% of eyes achieved an IOP ≤21 mmHg, with 42% maintaining this level without topical medication. Success rates declined with stricter IOP targets but did not differ significantly among secondary glaucoma subtypes. Mean IOP decreased significantly from 28.0 mmHg preoperatively to 13.6 mmHg at 12 months, corresponding to an average reduction of approximately 51%, and remained stable during long-term follow-up. Visual acuity and visual field parameters remained largely stable. Postoperative complications occurred in 26% of eyes and were predominantly transient; no intraoperative complications were observed. Removal of the intraluminal Prolene stent was associated with further IOP reduction without subtype-specific differences.

The PGI was associated with effective and sustained IOP reduction across a heterogeneous population of secondary glaucoma, with an acceptable complication profile in this retrospective cohort. These findings support the PGI as a useful surgical option for complex secondary glaucoma, although controlled comparative studies are needed to define its relative role among established GDDs.